Precious stohe



H. DE VRIES AND W. A. DONALDSON.

APPARATUS FOR GRINDING 0R POLISHING PRECIOUS STONES.

APPLICATION FILED JUNE 13| l9l8.

LSQB.

H. DE VRIES AND W. A. DONALDSON.

APPARATUS FO-R GRINDING 0R POLISHING PRECIOUS STONES. APPLICATION FILEDJUNE I3. 191s.

l SQ., f Patented May 27, 1919.

4/ 2 SHEETS-SHEEI 2. J' ,(5. F' ,4, +26 A7 47 g HARRYDE VRIES, F NEWARK,NEW JERSEY, AND W ILLIAM AaTHUa noisennson',

OF BRGOKIJ'YN, NEW YORK.

nPPenATUs non oninnm'e on Ponrsnine PRncIoUs sTonns Specification ofLetters Patent,

l Patented May 2'?, 1212.

Application filed .T une 13, 1.918. Serial No. 239,770.

To all whom t 'may concern Be it known that we, HARRY DE VRIES andWILLIAM ARTHUR DONALDSON, both citizens o f the United States, andresidents, respectively, of Newark,

` 1,243,491, granted to uson October 16,' 1917.

The object of the presentr invention is to provide a new and improvedapparatus for grinding 0r polishing diamondsand other preciousstones,and arranged to enable` thev operatorto quickly and accuratelyadjust the dop-holding device in an up and down direction to 'correctlylocate the .precious stone relative to the lap. Another object is topermit the wormnan to readily detach the dop-holding device from theframe and store it with the precious stone attached thereto during thenon-working hours in a safe, Vault, or similar place, and to re-attachthe dop-holding device at the beginning of the neXt work day to theframe and-in eX- actly the same position as it was in on removing ittherefrom. Another object is to simplify the construction of themounting of the dop holder in the carrier.

With these and other objects in view, the invention consists ofp certainnovell features of construction a's hereinafter shown and described andthen specifically pointed out lin the claims. 3

A practical embodiment of the invention is represented in theaccompanying drawings orming a part of this specification in whichsimilar characters of reference indicate corresponding parts in. all theviews. Y Figure l is aside elevationof the apparatus for grinding andpolishing precious stones;

Fig. 2 is a plan view of the saine;

by a set Fig. 3 is an enlarged sectional side elevation of the saine onthe line 3-3'of Fig. 2;

Fig. 4 is a cross section-of the saine on the line 4 4 of Fig. 1;

fFig. -5 lis an inverted plan view ofthe same; and

.f Fig. 6 is a sectional plan view of part of the same on the line 6-6of Fig. 1.

The lap 10 is arranged a short distance above a table 11 on which restthe legs 12 of the frame 13 supporting at its free end a dop-holdindevice 14 carrying the precious stone 15 to e ground or polished on theupper surface of the lap 10. rl'he frame 13 is provided near itsforward, end with a spirit level 16 of usual construction to enable theoperator to readily maintain the frame 13 in a horizontal position. Theframe 13 is provided at its rear end with the usual horizontallydisposed rod 20 held against lateral v displacement by abutting againsta vertical post 21 rising from the table 11.

The frame 13 is provided at its forward end with a bearing in which lismounted to slide u and down a hollow stein 26 pro# vided wit a key 27engaging a keyway arranged in the bearing 25 to hold the stem 26 againstturnin but to allow up and down movement of t e said stem. The frontface of the stem 26 is providediwi'th a flattened 28 (see Figs. 1, 4 and6) engaged j screw 29 screwing in the bearing 25 and adapted to securelyfasten/thestem 26 inthe adjusted position.

in thevhollow stem 26 is mounted to turn a spindle 30'provided at.itslower end with the web'31 of a sector 32, preferably in the form of adovetailed tongue engagedby a dovetailed vrgroove 33 (see Fig. 2)Jformed in a carrier 34 forming part of the dop-hold- -ing device 14.One or two'set screws 35 secure a collar 34 a ainst a liner 36 abuttingportion against one side o the sector 32 (see Fig 2) to securely holdthe carrier 34 in the desired adjusted position von the sector 32. Thespindle 30 of the sector 32 is provided at its upper end lwith a screwhaving a the upper end of the stem 26 to support the spindle 30 in thestem` 26, as will be readily lll? head 41 seated on-a shoulder 42 formedin understood by reference to Fig. 3. The spindle 30 is adapted to be4clamped 1n the dei vsired adjusted position by a clamping bar slide thecarrier 34 45 held in a slot 46 formed in the wall of the stem 26,` andthe said clamping bar 45 is engaged by a set screw 47 screwing in thebearing 25 and abutting against the said clamping bar 45 to force thelatter into firm engagement with the spindle 30. It will be noticed thatwhen the set screw 47 is loosened the spindle 30 can be readily turnedin the stem 26 to move the dop-holding device 14 into a desiredposition, and when this position has been reached the set screw 47 isscrewed up to clamp the spindle 30 in position in the stem 26 by theaction of the clamping bar 45. The lower end of the stem 26 is providedwith a collar 50 provided on its peripheral edge with a graduation 51corresponding to the points of -a compass, and a pointing mark 52 isarranged on the back of the sector web 31 to register with any one ofthe marks of the compass lgraduation 51 (see Fig. 4). The sector 32 isprovided on its peripheral face with a segmental gear wheel 60 in meshwith a pinion 61 secured 0n a Shaft 62 extending transversely andjournaled in the carrier 34. The front end of the shaft 62 is providedwith a head 63 adapted to 'be taken hold of by the operator for turningthe pinion 61 to aroundv on the sector 60 according to the direction inwhich the shaft 62 is turned at the time, it being, however, understoodthat during this adjusting movement of the carrier 34 on the sector 32the set screws 35 are loosened and after the desired adjustment is madethe set screws 35 are screwed up to lock the carrier 34 in position onthe sector 32.

The carrier 34 is provided with a pivot 70 preferably in the form of acup having a flange 71 at its upper end seated on a shoulder 72 formedon the carrier '34 (see Fig. The lower end of the pivot 70 projects intoa central recess'75 formed in a dop holder 76 mounted to turn on thesaid pivot 70. The top of the dop holder 7 6 abuts against the underside of the carrier 34 and a screw screws centrally into a centralbore78 in the dop holder 76.` The said screw 77 extends through the bottomof the pivot and is rovided with a head 79 against which a uts the upperen'd of a spring 80 seated at its lower end in the bottom of thecup-shaped pivot 70. By the arrange-` ment described the dop holder 76is mount# ed to turn on the pivot 70 and is held against' accidentalturning by frictional contact of its top with the under side of thecarrier 34 owing to thepressure of the spring 80. The face of the dopholder 76 is provided with a raised knurled band 81 adapted to be takenhold of by the operator to permit of coneral face of the dop 85 of thedop 86 carrying the precious stone 15 in the usual n1anner,"the said dop86 being securely held in position on the dop holder 76 by a set screw87 screwing in the lower end of the dop holder 76. The periphholder 76is provided with an annular graduation 88,- preferably in the forni ofthirty-two marks `spaced equal distances apart. A pointing mark 89 isar-` ranged. on the face of the carrier 34 (see Fig. 1) adapted toregister with any one of the marks of the graduation 88 on turning thedop holder 76 on the pivot 70, as above explained. It is understood thatthis graduation 88 serves to aid the operator to adjust the dopholder 76and consequently 4the dop 86 and the precious stone 15 carried thereby,to set the stone 15 in proper relation to -the lap 10 and to the numberof facets. 1t is further understood that the dop holder 76 can bereadily'turned on the carrier 34 owing to the yielding connection by theuse of the spring and the pivot 70- and at the same'time the dop holder76 is securely held in the adjusted position by frictional contact ofits dop with the under side of the carrier 34. x

In order to properly support the stone 15 in the dop hold'er 76 use ismade of the usual rod 90 provided with a claw 91 engaging the projectingend of the precious stone 15 held in the dop 86, as plainly indicated inFigs. 1, 3, 4 and 5. The rod 90 is held' adjustably 1n an up and downdirection in aY bracket 92 attached to the carrier 34, and the rod 90 isfastened in the adjusted position by a set screw 93 screwing in thebracket 92 and:

against the rod 90, as plainly shown in In order to indicate the exactangular position of the facets of the stone 15 relative to the face ofthe lap 1()v use is made of a degree scale 100 (see Fig. 1) marked onthe web 31 of the sector 32 and a pointing mark 101 is marked on theface of the carrier 34 to register with'any one ofthe degree marks onimparting a sliding motion to the carrier 34 on the sector 32, aspreviouslyexplained. When the several parts are in the position shown inthe drawings theny the mark 101 is opposite zero of the graduation 100and the axis of the dop 86 is vertical and parallel to the axis of thespindle 30, and in which spindle axis the center of the sector 32 islocated. downward on the sector 32 the position of the stone- 15relative to the lap 10 is correspondingly changed, 'the correspondingdegree of the scale 100 indicating the angle of a facet relative to theface of thc lap 10.

tenaces 'lhusl by the arrangement described, ltheop-A dle 30 carryingthe sector 32 andthe dop` holdingdevice 14 Vturnedole in the stem 26,

vit is evident that the stone l5 can be moved in Contact with dillerentportioris ofthe face of the lap 10 to allow` of utilizmg the entire faceof the lap 'for grindin will further loe-noticed that y the arrangementdescribed the dop-holding device can be readily vdetached from the frame13 on loosening the set screws 29 and 47. and sliding the-stem 26 out ofthe bearing 25. ,The dop-holding device can now be readily stored in asafe, vault or other place, with the 'precious stone attached to the dop86', and when it is desired to again proceed with the: grinding orpolishing'operation of the precious stone l5 Jit is only necessary forthe operator to remove the dop-holding device' from the storage placeand rengage the stem 26 with the bearing 25 and screw up the'set screws,29 and 47 to again fasten the4 dop-holding device in exactly the sameposition in the frame 15, that it had when it was removed therefrom forstoring purposesllt is understood that the distance the stem 26 ismoved: up or down in the bearing25 is readily determined by the positionof the spirit level 16 which when in central position .indicates thatthe frame 13 is in a horisfrontal position with the Astone. in contactwith the lap l0 and irrespective ofthe position or' the carrier 34 onthe sector32v or the position or the dop holder 76 on' the carrier 34l-laring4 thus described our invention, we claim as new and desiretosecure by Letters Patent A l.; ln an apparatus for grinding orpolishing preciousstones', a frame adapted* to'rest at one end on asupport and provided at its free end'vrith a bearing, a hollow stemadjustably secured in the said bearing,a sector having a spindle mountedto turn in the said hollow stem,`a .clamping member held in the c/saidstern and engaging the said spindle, a

set screw "screwing in the said bearing f againstv the said clampingmember to torce the latter in clamping contact with the said. spindle tohold the latter against turning in the stem, and a dop-holding meansadjustahly secured to the said sector.

2. ln apparatus for grinding or polishing precious stones, a iframeadapted to rest at one end' a horizontal support and provided at itsother end with a hearing having a lreyway, a hollow stem slidable up ordown in the said hearing and having a'lrey engaging the said'leyway,means for adjustahiy securing the stern in the bearing, a sectorpurposes. lty

provided with a spindle mounted to turn in the said 'hollow stem, meansforsecuring the spindle in and to the sleeve, means fastening .the saidspindle inposition against turning in the said stem, a carrier mountedto slide on the said sector, a dop holder mounted to turn onthe saidcarrier, and a dop removably held onthe said dop holder.

3. ln anapparatus y:i'or grinding or polishing precious stones, a frameadapted to rest at one end on a horizontal support and provided at itsother end with a bearing having a keyway, a hollow stem slidable up ordown in the said bearing and having a key engaging the said keyway, thesaid stem having a collar provided with aI compass graduation, asectorhaving a pointing mark and provided 'with a spindle mounted to turn inthc said hollow stem, means fastening the said spindle in positionagainst turning in the said stem, a carrier mounted to slide on the saidsector, a dop holder mounted to turn on the saidlcarrier, and a dopremovably held on the said dop holder.

4, ln an apparatus for. grinding and pol- -ishoing preciousstones, asupport, a carrier adjustably mounted in the support, a cupshaped pivotcarried by the carrier, a dop holder engaging the carrier and having itsupper end. recessed to receive the pivot, a screw passing through thepivot and screwing into the dop holder, a spring surrounding the screwbetween its head and the 'bottom of thev cup, and a dop carried by thesaid holder.

5.., ln an apparatus for grinding and polishing preclous stones, asupport, a carrier Iladjustalolymounted on the support, a cupl shapedpivot carried by thev carrier, a dop holder abutting against the carrierand provided, with a bore having its upper end recessed to receive thecup-shaped pivot, a screw passingthrough the cup-shaped pivot andscrewing into the bore of the dop holder, a spring surrounding thescrewin the pivot between the bottom thereoic and the head of i thestern, a clamp bar in the slot or the stemand engaging the spindle, aset screw mounted in the bearing and engaging the clamping har l dopholding means adiustahly mounted on the sector.

7. ln an apparatus for grinding and polishing precious stones, a 'l'rameprovided slide but not to turn in the bearing and provided with an 0eniug and internal shoulder at it's upper end), a sei; screw foradjustably securing the stem in the bearing, a dop holding device havinga member provided with a spindle extending into the stem, a screwscrewing into the upper end of the spindle set screw engaging theclamping bar.

. HARRY mi VRIES.

WILLIAM ARTHUR DONALDSN.

